package com.mt.common.util;

import org.slf4j.LoggerFactory;

import javax.crypto.Cipher;
import java.io.ByteArrayOutputStream;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;

/** */

/**
 * <p>
 * RSA公钥/私钥/签名工具包
 * </p>
 * <p>
 * 罗纳德·李维斯特（Ron [R]ivest）、阿迪·萨莫尔（Adi [S]hamir）和伦纳德·阿德曼（Leonard [A]dleman）
 * </p>
 * <p>
 * 字符串格式的密钥在未在特殊说明情况下都为BASE64编码格式<br/>
 * 由于非对称加密速度极其缓慢，一般文件不使用它来加密而是使用对称加密，<br/>
 * 非对称加密算法可以用来对对称加密的密钥加密，这样保证密钥的安全也就保证了数据的安全
 * </p>
 * 
 * @author IceWee
 * @date 2012-4-26
 * @version 1.0
 */
public class RSAUtil {
    private static final org.slf4j.Logger LOGGER = LoggerFactory.getLogger(RSAUtil.class);

    /** */
    /**
     * 加密算法RSA
     */
    public static final String KEY_ALGORITHM = "RSA";

    /** */
    /**
     * 签名算法
     */
    public static final String SIGNATURE_ALGORITHM = "MD5withRSA";

    /** */
    /**
     * 获取公钥的key
     */
    private static final String PUBLIC_KEY = "RSAPublicKey";

    /** */
    /**
     * 获取私钥的key
     */
    private static final String PRIVATE_KEY = "RSAPrivateKey";

    /** */
    /**
     * RSA最大加密明文大小
     */
    private static final int MAX_ENCRYPT_BLOCK = 117;

    /** */
    /**
     * RSA最大解密密文大小
     */
    private static final int MAX_DECRYPT_BLOCK = 128;

    private static final String publicKey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCEjG1nKiIXSfUlUrxEmSteD0RqtAZj+G8Qiq8XINKnl+K6An2GNka6n24qmsuT/vnSSKjXG35MwiTmwn152ic4gL4Kw6KoHr+kw+/znAAkp+yiyj4KFO9h7zqrB7a5+om/dCzNC9JZlSSJXybAw8C2vRpPgTVnUMXWXRqKfpX4qQIDAQAB";

    private static final String privateKey = "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";

    /** */
    /**
     * <p>
     * 生成密钥对(公钥和私钥)
     * </p>
     * 
     * @return
     * @throws Exception
     */
    public static Map<String, Object> genKeyPair() throws Exception {
        KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM);
        keyPairGen.initialize(1024);
        KeyPair keyPair = keyPairGen.generateKeyPair();
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        Map<String, Object> keyMap = new HashMap<String, Object>(2);
        keyMap.put(PUBLIC_KEY, publicKey);
        keyMap.put(PRIVATE_KEY, privateKey);
        return keyMap;
    }

    /** */
    /**
     * <p>
     * 用私钥对信息生成数字签名
     * </p>
     * 
     * @param data
     *            已加密数据
     * @param privateKey
     *            私钥(BASE64编码)
     * 
     * @return
     * @throws Exception
     */
    public static String sign(byte[] data, String privateKey) throws Exception {
        byte[] keyBytes = Base64Utils.decode(privateKey);
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        PrivateKey privateK = keyFactory.generatePrivate(pkcs8KeySpec);
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initSign(privateK);
        signature.update(data);
        return Base64Utils.encode(signature.sign());
    }

    /** */
    /**
     * <p>
     * 校验数字签名
     * </p>
     * 
     * @param data
     *            已加密数据
     * @param publicKey
     *            公钥(BASE64编码)
     * @param sign
     *            数字签名
     * 
     * @return
     * @throws Exception
     * 
     */
    public static boolean verify(byte[] data, String publicKey, String sign) throws Exception {
        byte[] keyBytes = Base64Utils.decode(publicKey);
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        PublicKey publicK = keyFactory.generatePublic(keySpec);
        Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM);
        signature.initVerify(publicK);
        signature.update(data);
        return signature.verify(Base64Utils.decode(sign));
    }

    /** */
    /**
     * <P>
     * 私钥解密
     * </p>
     * 
     * @param encryptedData
     *            已加密数据
     * @param privateKey
     *            私钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] decryptByPrivateKey(byte[] encryptedData, String privateKey) throws Exception {
        byte[] keyBytes = Base64Utils.decode(privateKey);
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key privateK = keyFactory.generatePrivate(pkcs8KeySpec);
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.DECRYPT_MODE, privateK);
        int inputLen = encryptedData.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段解密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
                cache = cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_DECRYPT_BLOCK;
        }
        byte[] decryptedData = out.toByteArray();
        out.close();
        return decryptedData;
    }

    /** */
    /**
     * <p>
     * 公钥解密
     * </p>
     * 
     * @param encryptedData
     *            已加密数据
     * @param publicKey
     *            公钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] decryptByPublicKey(byte[] encryptedData, String publicKey) throws Exception {
        byte[] keyBytes = Base64Utils.decode(publicKey);
        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key publicK = keyFactory.generatePublic(x509KeySpec);
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.DECRYPT_MODE, publicK);
        int inputLen = encryptedData.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段解密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
                cache = cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_DECRYPT_BLOCK;
        }
        byte[] decryptedData = out.toByteArray();
        out.close();
        return decryptedData;
    }

    /** */
    /**
     * <p>
     * 公钥加密
     * </p>
     * 
     * @param data
     *            源数据
     * @param publicKey
     *            公钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] encryptByPublicKey(byte[] data, String publicKey) throws Exception {
        byte[] keyBytes = Base64Utils.decode(publicKey);
        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key publicK = keyFactory.generatePublic(x509KeySpec);
        // 对数据加密
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.ENCRYPT_MODE, publicK);
        int inputLen = data.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段加密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
                cache = cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(data, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_ENCRYPT_BLOCK;
        }
        byte[] encryptedData = out.toByteArray();
        out.close();
        return encryptedData;
    }

    /** */
    /**
     * <p>
     * 私钥加密
     * </p>
     * 
     * @param data
     *            源数据
     * @param privateKey
     *            私钥(BASE64编码)
     * @return
     * @throws Exception
     */
    public static byte[] encryptByPrivateKey(byte[] data, String privateKey) throws Exception {
        byte[] keyBytes = Base64Utils.decode(privateKey);
        PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);
        Key privateK = keyFactory.generatePrivate(pkcs8KeySpec);
        Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
        cipher.init(Cipher.ENCRYPT_MODE, privateK);
        int inputLen = data.length;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        int offSet = 0;
        byte[] cache;
        int i = 0;
        // 对数据分段加密
        while (inputLen - offSet > 0) {
            if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
                cache = cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);
            } else {
                cache = cipher.doFinal(data, offSet, inputLen - offSet);
            }
            out.write(cache, 0, cache.length);
            i++;
            offSet = i * MAX_ENCRYPT_BLOCK;
        }
        byte[] encryptedData = out.toByteArray();
        out.close();
        return encryptedData;
    }

    /** */
    /**
     * <p>
     * 获取私钥
     * </p>
     * 
     * @param keyMap
     *            密钥对
     * @return
     * @throws Exception
     */
    public static String getPrivateKey(Map<String, Object> keyMap) throws Exception {
        Key key = (Key) keyMap.get(PRIVATE_KEY);
        return Base64Utils.encode(key.getEncoded());
    }

    /** */
    /**
     * <p>
     * 获取公钥
     * </p>
     * 
     * @param keyMap
     *            密钥对
     * @return
     * @throws Exception
     */
    public static String getPublicKey(Map<String, Object> keyMap) throws Exception {
        Key key = (Key) keyMap.get(PUBLIC_KEY);
        return Base64Utils.encode(key.getEncoded());
    }

    public static String encrypt(String source) throws Exception {
        System.err.println("公钥加密——私钥解密");
        // source =
        // "{\"buyerMob\":\"123654\",\"cgstPer\":0.0,\"cgstVal\":0.0,\"channelType\":\"B2C\",\"customerAddressId\":212,\"customerId\":247,\"customerVirtualId\":0,\"empUserId\":0,\"igstPer\":0.0,\"igstVal\":0.0,\"isVirtualOrder\":0,\"orderDetailB2CEntityList\":[{\"cgstPer\":0.0,\"cgstVal\":0.0,\"groupId\":0,\"isSelected\":false,\"orderDiscPer\":0.0,\"orderDiscValue\":0.0,\"orderOrigValue\":0.0,\"prodColor\":\"01\",\"prodId\":2889,\"prodImage\":\"https://s3.ap-south-1.amazonaws.com/mmimage/products/200500034/200500034a.jpg_size_800.jpeg\",\"prodName\":\"Liquid
        // Eyeliner Waterproof Long Lasting Eyes
        // Makeup\",\"prodPrice\":99.0,\"prodQty\":1,\"prodSize\":\"17*7.5*1cm\",\"skuId\":\"20050003401\",\"baseData\":{}}],\"orderDiscPer\":0.0,\"orderDiscValue\":0.0,\"orderGeneratedBy\":\"Android\",\"orderOrigValue\":0.0,\"orderQty\":0.0,\"orderStatus\":0,\"orderValue\":0.0,\"orderValueCurrId\":0,\"paymentMode\":\"COD\",\"prodVal\":0.0,\"ratePerKg\":0.0,\"sgstPer\":0.0,\"sgstVal\":0.0,\"shipmentStatus\":0,\"shippingCost\":0.0,\"shippingTotalWeight\":0.0,\"taxVal\":0.0,\"baseData\":{}}";
        String encResult = null;
        try {
            byte[] data = source.getBytes();
            byte[] encodedData = RSAUtil.encryptByPublicKey(data, publicKey);
            encResult = new String(Base64Utils.encode(encodedData));
            LOGGER.info("公钥加密——私钥解密,加密后文字：\n{}", encResult);
        } catch (Exception e) {
            LOGGER.error("RSAUtil encrypt Error!", e);
        }

        return encResult;
    }

    public static String decrypt(String source) throws Exception {
        System.err.println("公钥加密——私钥解密");
        String decResult = null;
        try {
            byte[] decodedData = RSAUtil.decryptByPrivateKey(Base64Utils.decode(source), privateKey);
            decResult = new String(decodedData);
            LOGGER.info("公钥加密——私钥解密,解密后文字: \n{}", decResult);
        } catch (Exception e) {
            LOGGER.error("RSAUtil decrypt Error!", e);
        }

        return decResult;
    }

    static void testSign() throws Exception {
        System.err.println("私钥加密——公钥解密");
        String source = "这是一行测试RSA数字签名的无意义文字";
        System.out.println("原文字：\r\n" + source);
        byte[] data = source.getBytes();
        byte[] encodedData = RSAUtil.encryptByPrivateKey(data, privateKey);
        System.out.println("加密后：\r\n" + new String(encodedData));
        byte[] decodedData = RSAUtil.decryptByPublicKey(encodedData, publicKey);
        String target = new String(decodedData);
        System.out.println("解密后: \r\n" + target);
        System.err.println("私钥签名——公钥验证签名");
        String sign = RSAUtil.sign(encodedData, privateKey);
        System.err.println("签名:\r" + sign);
        boolean status = RSAUtil.verify(encodedData, publicKey, sign);
        System.err.println("验证结果:\r" + status);
    }

    public static void main(String[] args) throws Exception {
        decrypt("K1MKdqVzrNrFiXM1RKsTApU1jfiyiWzgDj+5sZKJPAxBazMNHnva+Itu/ePIGji4WKxUwfdZjkwJXYaA76l5nqNRrpZ+SCz7itjWkNDAbLw8d135BNAD2BVuJoTs3AIphy3bbjhbZhSA5RiihFM0Xn2b+TNYjuhmbgeWyKWCLQ0=");
        // testSign();
    }
}
